[RFC] Rename Hybrid Script

One thing that is worth considering is how are we going to parse a module with mixed relay and tir functions (or those with external ones).

@tvm.script
class MixedModule:
     def relay_func(x: ty.Tensor):
         return relay.call_tir_dest_passing(tir_func, x)
   
     def tir_func(x: ty.handle)
          ...

Having such mixed module(and unified design) is a motivation for a common decorator. Although I agree we need to think about ways to distinguish the two.